Christopher Graham said on Friday the News International subsidiary had told him that, contrary to the earlier claims of a senior executive, it had not transferred archived emails to India and none had been lost.

"We have received assurances from News Group Newspapers (NGN) that in fact no emails were transferred to India," Graham said in a statement. He added he had "seen no evidence to contradict this assurance".

Bob Bird, the editor of the News of the World Scotland, said when he gave evidence during the libel trial of Scottish politician Tommy Sheridan last year that emails sought by his defence team had gone missing in a botched transfer to India.

They cover a two-year period in 2005 and 2006 when private investigator Glenn Mulcaire, who was on the News of the World's books, was hacking into mobile phones belonging to a number of public figures.

The Data Protection Act, which the ICO is responsible for overseeing and enforcing, contains strict rules on transferring personal data.

It also requires companies and organisation to keep data secure. The ICO received a complaint last year from Labour MP and former minister Tom Watson, who claimed News Group might have been breached the terms of the act.

Graham said News Group had declined to answer his questions about the alleged loss and subsequent recovery of the emails, citing legal action currently being pursued by victims of phone hacking in the high court.

"We have asked NGN to provide us with meaningful answers to questions about the alleged loss and apparent subsequent recovery of the emails", he added. "However, they have declined to do so because the matters in question remain sub judice pending final decisions being made in respect of an appeal application."

Graham added: "Given that the matter remains sub judice and there is a lack of firm evidence that the emails were actually lost or that any damage or distress has been caused to the data subjects of the emails, my investigation is closed".

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